I mean tbf if a single country adopted socialism it would still have a GDP of some kind as long as there was the need for goods that came from outside the country. Hell you could have the ideal communist society but would still have to trade for something because no land on earth has all of the resources a modern society needs.
Socialism, commonly known for the very little, unimportant factor of having workers own the means of production, now includes a stock market where people can buy a share of the means of production, using capital, without ever having worked there, or anywhere, ever?
In Hungary, a lot of companies are state owned*, I guess I now live in a communist utopia under comrade Viktor Orbán.
* at max 25%, only so the losses can be subsidized by the state, and old people that wanted "the good old days" back could cheer that "the industries were nationalized".
If the public doesn't control the political parties or their political orientation through voting or councils, socialism is pretty useless, it could even be argued that a society with an illiberal state cannot be socialist, because while it may not have an owning class it sure has a bureaucratic ruling class.
Read: The Average Joe in China cannot decide what their workplace is doing.